Free Tool
Late Fee Calculator
Calculate interest and late fees on overdue invoices based on your state's laws.
Calculation Results
Original Invoice $0.00
Interest Accrued $0.00
Flat Late Fee $0.00
Total Due $0.00
Formula: Interest = (Principal × Rate × Days) ÷ 365
Important Disclaimer
This calculator is for educational purposes only. It is not legal or financial advice. Late fee laws vary by state and contract terms. Always consult with a qualified attorney before charging late fees. Verify that your contract terms comply with your state's usury laws.
Know Your State's Laws
Check the maximum interest rates and late fee rules for your state.
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